audit.4 revision 155392
Copyright (c) 2006 Robert N. M. Watson
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.

$FreeBSD: head/share/man/man4/audit.4 155392 2006-02-06 18:41:00Z rwatson $

.Dd February 6, 2006 .Os .Dt AUDIT 4 .Sh NAME .Nm audit .Nd Security Event Audit .Sh SYNOPSIS .Cd "options AUDIT" .Sh DESCRIPTION Security Event Audit is a facility to provide fine-grained, configurable logging of security-relevant events, and is intended to meet the requirements of the Common Criteria (CC) Common Access Protection Profile (CAPP) evaluation. The .Fx audit facility implements the de facto industry standard BSM API, file formats, and command line interface, first found in the Solaris operating system. Information on the user space implementation can be found in .Xr libbsm 3 .

p Audit support is enabled at boot, if present in the kernel, using an .Xr rc.conf 5 flag. The audit daemon, .Xr auditd 8 , is responsible for configuring the kernel to perform audit, pushing configuration data from the various audit configuration files into the kernel. .Ss Audit Special Device The kernel audit facility provides a special device,

a /dev/audit , which is used by .Xr auditd 8 to monitor for audit events, such as requests to cycle the log, low disk space conditions, and requests to terminate auditing. This device is not intended for use by applications. .Ss Audit Pipe Special Devices The kernel audit facility also a clonable special device,

a /dev/auditpipe , which allows appropriately privileged applications to gain direct access to the BSM audit stream without accessing audit trail files. As audit trail files are owned by the audit daemon until terminated, they are an unreliable way for applications to access live audit data; this special device inserts a "tee" in the audit event stream. This facility is appropriate for use by live monitoring tools, including intrusion detection. As the device is clonable, more than one instance of the device may be opened at a time; each device instance will provide access to all records.

p The audit pipe device provides discreet BSM audit records; if the read buffer passed by the application is too small to hold the next record in the sequence, it will be dropped. Unlike audit data written to the audit trail, the reliability of record delivery is not guaranteed. In particular, when an audit pipe queue fills, records will be dropped. Audit pipe devices are blocking by default, but support non-blocking I/O, asynchronous I/O using SIGIO, and support for polled operation via .Xr select 2 and .Xr poll 2 . .Sh SEE ALSO .Xr auditreduce 1 , .Xr praudit 1 , .Xr audit 2 , .Xr auditctl 2 , .Xr auditon 2 , .Xr getaudit 2 , .Xr getauid 2 , .Xr poll 2 , .Xr select 2 , .Xr setaudit 2 , .Xr setauid 2 , .Xr libbsm 3 , .Xr audit.log 5 , .Xr audit_class 5 , .Xr audit_control 5 , .Xr audit_event 5 , .Xr audit_user 5 , .Xr audit_warn 5 , .Xr rc.conf 5 , .Xr audit 8 , .Xr auditd 8 .Sh AUTHORS This software was created by McAfee Research, the security research division of McAfee, Inc., under contract to Apple Computer Inc. Additional authors include Wayne Salamon, Robert Watson, and SPARTA Inc.

p The Basic Security Module (BSM) interface to audit records and audit event stream format were defined by Sun Microsystems.

p This manual page was written by .An Robert Watson Aq rwatson@FreeBSD.org . .Sh HISTORY The OpenBSM implementation was created by McAfee Research, the security division of McAfee Inc., under contract to Apple Computer Inc. in 2004. It was subsequently adopted by the TrustedBSD Project as the foundation for the OpenBSM distribution.

p Support for kernel audit first appeared in .Fx 6.1 . .Sh BUGS The audit facility in .Fx is considered experimental, and production deployment should occur only after careful consideration of the risks of deploying experimental software.

p The .Fx kernel does not fully validate that audit records submitted by user applications are syntactically valid BSM; as submission of records is limited to privileged processes, this is not a critical bug.

p Instrumentation of auditable events in the kernel is not complete, as some system calls do not generate audit records, or generate audit records with incomplete argument information.

p Mandatory Access Control (MAC) labels, as provided by the .Xr mac 4 facility, are not audited as part of records involving MAC decisions.